Chernobyl reactor accident consequences on small atmospheric ions concentration above Athens

In the present study the variation in small ion concentration (SIC), positive and negative, above Athens (=37°58.3N, =23°43E,h=107 m) after Chernobyl reactor accident is examined.SIC started to increase importantly at the National Observatory of Athens (N.O.A) since 3 May 1986 and reached its highest mean daily values on Monday, 5 May. These maximum values were 4 times the normal for positive ions and 5 times the normal for negative ions. Correlation coefficients were calculated between SIC and radionuclides I-131, Cs-137, Ru-103 and outdoor exposure rate.